Semiconductor photodetectors, such as P-I-N diode photodetectors, require a low capacitance for certain applications. The requirement for a low capacitance imposes a requirement for a small aperture size. For instance, if the capacitance of the photodetector is required to be under 100 fF, it is common that the corresponding aperture size will need to be around or lower than 30 um in diameter. Requiring a small area of light detection inflicts challenges for optical alignment and optical tolerances—especially in optical communication systems that utilize optical fibers.